US 2008/0315331 A1 discloses a transducer assembly having a ground connection routed through a via formed in a cMUT array and through an ASIC. A transducer module comprises a cMUT transducer subarray formed on a semiconductor substrate with a front electrode positioned over a membrane and with the membrane suspended over insulating supports. The individual cells include bottom electrodes for receiving signals from ASIC circuit cells. A conductive via is formed within the insulating support between adjacent transducer cells to connect the front electrode to a contact on the cMUT substrate. However, the transducer assembly disclosed in US 2008/0315331 A1 is quite complex and thus not easy in manufacturing.